At dawn this morning our expert climbers in inflatable speed boats dodged Danish Navy commandos before climbing up the inside of the rig and hanging from it in tents suspended from ropes, halting its drilling operation.

The climbers have enough supplies to occupy the hanging tents for several days. If they succeed in stopping drilling for just a short time then the operators, Britain's Cairn Energy, will struggle to meet a tight deadline to complete the exploration before winter ice conditions force it to abandon the search for oil off Greenland until next year.